- Consuming, or have consumed in the last 3 months, medications or nutritional supplements which are known to affect lipid metabolism (such as cholestyramine, colestipol, niacin, clofibrate, gemfibrozil, probucol, HMG-CoA R inhibitors, methotrexate, high dose dietary supplements, fish oil capsules or plant sterol or stanol), or have any dietary restrictions which would prevent them from consuming the trial treatments